“He pretty much just ran me through a seminar on technique,” Castillo told MMAjunkie.com Radio (www.mmajunkie.com/radio).

Castillo vs. Sass is part on the Facebook-streamed preliminary card before main-card fights on FUEL TV.

Onetime lightweight title challenger Diaz is not only a top-flight competitor in Castillo’s division, but he boasts seven submission wins in the UFC. The most featured performance on his highlight reel is a triangle choke of Kurt Pellegrino at UFC Fight Night 13. So confident is he of the hold that he frees his hands to celebrate with a double-bird salute.

“If there’s anyone you want to learn from to stop the triangle, it’s that man,” said Castillo, who at the time of the interview was a few days away from a trip to Diaz’s hometown in Stockton, Calif. “He’s got thousands and thousands of dollars of bonus money from that triangle.”

Castillo needs the help. While Diaz might have more money in his pockets, Sass has more triangles on his resume. Nine to be exact, and three by heel hook for good measure. In his most recent performance at UFC on FX 5, the Brit suffered his first loss inside the octagon in a fight against the more experienced Matt Wiman, who turned the tables on him and cinched an armbar in the first round.

Castillo, too, is on the rebound after a quick knockout loss to Michael Johnson at UFC on FUEL TV 5. Prior to that, he earned three consecutive victories in the UFC and was on his way toward title contention. But the college wrestler is not deterred.

“I think it’s just where I’m at,” he said. “In the UFC and WEC, there’s just a great talent pool of lightweight fighters. I feel some of the fights were easier for me in terms of style, but in general, I’ve fought some of the best guys in the world. My record is not the best record, and I’m not happy about it. But the losses I’ve had were tough guys. But just being a part of the UFC is a like a dream come true.

“As a kid, I thought I was going to be a professional athlete, but in my head, it was basketball. But when I got into the eighth grade, and I was 5-foot-3, I started to reevaluate things. I found myself in a wrestling room, and that better suited my height.”

Castillo’s compact frame could be a plus heading into his bout with Sass. With shorter limbs to grab ahold of, only his neck is in danger.

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